Are obese children under reporting what they eat? Yoni Freedhoff, MD blasts a recently published study suggesting that obese children may even eat less than leaner peers. Is it really so preposterous that thinner kids may eat more than their obese counterparts?
To be fair, asking 7 and 10 year old children to report what they eat is probably even more unreliable than asking adults. The data isn’t good. But data I see shows that everyone under reports, at all points of the BMI spectrum.
My real concern here is that there is no consideration of other factors that influence what the body does with those calories. The scientific community should consider calorie intake, but needs to also look beyond calories. They need to consider the wider scope of factors that influence obesity in our children and everyone else.
A ROLE FOR INSULIN RESISTANCE
One of those issues is something we call “nutrient partitioning.” People who are more insulin resistant tend to preferentially store calories as fat.
Insulin resistant people secret more insulin in response to the same load of carbohydrate compared to insulin sensitive folks. This insulin surge drives fat accumulation, as if the body was taking advantage of the “harvest” and storing for winter. In one study published in 2011, it was the children with a lower BMI (and presumably the more insulin sensitive children) who reported eating more candy, more sugar, and more calories.
Another study published in 2009 showed a very different interesting response to the composition of the diet. Some kids (typically those with a lower BMI with much greater insulin sensitivity) ate a high carbohydrate breakfast and felt satisfied for hours. Kids with the higher BMI and higher insulin levels–eating the same breakfast– felt hungry in 30-60 minutes. Only when the heavier kids ate more protein in the morning, did they feel satisfied as long as their thinner counterparts.
When energy from breakfast preferentially gets stored as fat, blood sugar dives. That someone is going to feel hungry again–sometimes in as little as 30-60 minutes after eating a meal. At the same time, the elevated insulin levels literally block fat from being mobilized for fuel. No wonder insulin resistant types feel like it takes a herculean effort to lose a pound.
A ROLE FOR GUT MICROBES
Another explanation could be the role of the bacteria in our gut. Scientific reports suggest that thin people tend to house a different a ratio of beneficial bacteria in their gut compared to their heavier counterparts. Researchers suggest that the relative proportion of Bacteroidetes is decreased in obese people by comparison with lean people. Firmacutes are in higher proportion in heavier people.
In addition studies suggest that diet plays a significant role in which bacteria strain thrives. At one symposium, a researcher representing Hi Maize Resistant Starch pointed to refined carbohydrate in the American diet as a significant influence. With more resistant starch, the heavier individuals lost more weight.
A ROLE FOR ENDOCRINE DISRUPTORS
The topic getting the least attention is also probably the one that is the most overwhelming. We are polluting our environment with substances that interfere with normal metabolism. These agents are known as obesogens, endocrine disruptors (ED) and persistent organic pollutants (POPs) They disrupt thyroid function, compromise glucose tolerance and are linked to higher incidence of all kinds of metabolic disease, including diabetes, obesity, heart disease and even cancer.
As the the entire global population becomes more obese, it seems less and less likely that just calories and a refined Western diet is to blame. I have a hard time believing that even the extremely poor are eating “too much” fast food and junk, especially as leaner counterparts are eating the same thing.
TEASING OUT THE TRUTH
The tricky part is that not all people gain weight on refined carbohydrate intake. Not everyone feels hungrier after eating refined carbohydrate. And not all insulin resistant people are heavy.
All of these observations lead me to believe that relying on calorie counts to explain why some are fat and and some are thin is simplistic at best. I wonder when scientists and clinicians will openly appreciate how much we still don’t know and look beyond the calorie balance equation. It seems more blinded than ever to believe the answer to obesity is simply eat less, exercise more.